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	<head>
		<title>three.js webgpu - custom fog background</title>
		<meta charset="utf-8">
		<meta name="viewport" content="width=device-width, user-scalable=no, minimum-scale=1.0, maximum-scale=1.0">
		<link type="text/css" rel="stylesheet" href="main.css">
		<style>

			#info {
				background-color: #0066ff;
			}

		</style>
	</head>
	<body>

		<div id="info">
			<a href="https://threejs.org" target="_blank" rel="noopener">three.js</a> webgpu - custom fog background<br />
			Battle Damaged Sci-fi Helmet by
			<a href="https://sketchfab.com/theblueturtle_" target="_blank" rel="noopener">theblueturtle_</a><br />
			<a href="https://hdrihaven.com/hdri/?h=royal_esplanade" target="_blank" rel="noopener">Royal Esplanade</a> by <a href="https://hdrihaven.com/" target="_blank" rel="noopener">HDRI Haven</a>
		</div>

		<script type="importmap">
			{
				"imports": {
					"three": "../build/three.webgpu.js",
					"three/tsl": "../build/three.webgpu.js",
					"three/addons/": "./jsm/"
				}
			}
		</script>

		<script type="module">

			import * as THREE from 'three';
			import { pass, color, rangeFog } from 'three/tsl';

			import { RGBELoader } from 'three/addons/loaders/RGBELoader.js';

			import { OrbitControls } from 'three/addons/controls/OrbitControls.js';
			import { GLTFLoader } from 'three/addons/loaders/GLTFLoader.js';

			let camera, scene, renderer;
			let postProcessing;

			init();

			function init() {

				const container = document.createElement( 'div' );
				document.body.appendChild( container );

				camera = new THREE.PerspectiveCamera( 45, window.innerWidth / window.innerHeight, 0.25, 20 );
				camera.position.set( - 1.8, 0.6, 2.7 );

				scene = new THREE.Scene();

				renderer = new THREE.WebGPURenderer( { antialias: true } );
				renderer.setPixelRatio( window.devicePixelRatio );
				renderer.setSize( window.innerWidth, window.innerHeight );
				//renderer.toneMapping = THREE.ACESFilmicToneMapping; // apply tone mapping in post processing
				container.appendChild( renderer.domElement );

				// post processing

				// render scene pass ( the same of css )
				const scenePass = pass( scene, camera );
				const scenePassViewZ = scenePass.getViewZNode();

				// background color
				const backgroundColor = color( 0x0066ff );

				// get fog factor from scene pass context
				// equivalent to: scene.fog = new THREE.Fog( 0x0066ff, 2.7, 4 );
				const fogFactor = rangeFog( null, 2.7, 4 ).context( { getViewZ: () => scenePassViewZ } );

				// tone mapping scene pass
				const scenePassTM = scenePass.toneMapping( THREE.ACESFilmicToneMapping );

				// mix fog from fog factor and background color
				const compose = fogFactor.mix( scenePassTM, backgroundColor );

				postProcessing = new THREE.PostProcessing( renderer );
				postProcessing.outputNode = compose;

				//

				new RGBELoader()
					.setPath( 'textures/equirectangular/' )
					.load( 'royal_esplanade_1k.hdr', function ( texture ) {

						texture.mapping = THREE.EquirectangularReflectionMapping;

						scene.environment = texture;

						// model

						const loader = new GLTFLoader().setPath( 'models/gltf/DamagedHelmet/glTF/' );
						loader.load( 'DamagedHelmet.gltf', function ( gltf ) {

							scene.add( gltf.scene );

							render();

						} );

					} );

				//

				const controls = new OrbitControls( camera, renderer.domElement );
				controls.minDistance = 2;
				controls.maxDistance = 5;
				controls.target.set( 0, - 0.1, - 0.2 );
				controls.update();
				controls.addEventListener( 'change', render ); // use if there is no animation loop

				window.addEventListener( 'resize', onWindowResize );

			}

			function onWindowResize() {

				camera.aspect = window.innerWidth / window.innerHeight;
				camera.updateProjectionMatrix();

				renderer.setSize( window.innerWidth, window.innerHeight );

				render();

			}

			//

			function render() {

				postProcessing.renderAsync();

			}

		</script>

	</body>
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